1) Why is opamp called a direct coupled (dc coupled) amplifier ?
2) A normal voltage or curent amplifier provides power gain...then why do we go for power amplifiers for increased power ? cant we use a cascaded amplifier stage to achieve the required power ?
3) How is the digital ground different from analog ground ?
4) How is a cmos inverter an amplifier ?

1) Why is opamp called a direct coupled (dc coupled) amplifier ?
2) A normal voltage or curent amplifier provides power gain...then why do we go for power amplifiers for increased power ? cant we use a cascaded amplifier stage to achieve the required power ?
3) How is the digital ground different from analog ground ?
4) How is a cmos inverter an amplifier ?

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